Heart failure (HF) affects 5-6 million Americans and, despite recent pharmacological and technological advances, is increasing in epidemic proportions as the population ages. Patients with HF suffer from debilitating symptoms and a loss of quality of life. Somatic symptoms such as fatigue and sleep disturbances are common among HF patients, which are ironically associated with physical inactivity and can create a spiraling decline in physical and cardiac function and even worse quality of life. Thus, behavioral/lifestyle interventions that increase physical activity may improve cardiac function and quality of life in this group. Historically, HF patients were counseled to limit physical activities, but recent studies show that moderate exercise can be performed safely in properly evaluated NYHA II-III HF patients. However, most traditional exercise intervention studies in HF have been conducted on relatively young patients with little comorbidity, and such programs are unsuitable for many older frail HF patients. Conversely, tai chi has been practiced for centuries by all age groups for wellness and to maintain health. Tai chi is ideal for HF patients because it is composed of mindfully meditative movements that generate an aerobic work-out, permits adjustable levels of intensity by using larger or smaller movements, improves balance, works the whole body, and is well tolerated in HF patients. Indeed, findings from our recently completed R21 pilot project indicate that tai chi leads to reductions in somatic symptoms, including fatigue, and increases physical function as measured by the distance walked in a 6-minute walk task. Until now, tai chi studies involving HF patients have been small more preliminary investigations and have not examined important clinical and functional measures relevant to HF. While standard exercise intervention studies in HF have found increases in ejection fraction (EF) and reduced end diastolic volume (EDV) and end systolic volume (ESV), tai chi's efficacy for improvements in cardiac functional capacity still need to be examined. Thus, the objective of our study is to determine if tai chi will benefit HF patients by increasing physical function, cardiac functional capacity, and HF related quality of life. The proposed study will consist of two groups (N = 68 HF patients/group), a 16-week, twice weekly tai chi class using a Manual developed by our R21 grant specifically for HF patients. A health education comparison group will meet for a comparable duration, and also have a standardized list of topics used for the classes. This group is created to control for attention and social interactions of the tai chi intervention. Although there is evidence that changes in specific behavioral activities improve quality of life in HF patients, most current healthcare insurance in the United States (including Medicare), does not pay for HF rehabilitation. The findings of our investigation will help identify the efficacy of tai chi as an option for current HF management and further our understanding of the mechanisms. Thus, this study also has the benefit of evaluating an intervention that will improve HF disease severity and related quality of life outcomes that could impact health policy.